The present invention relates to a switching device of a breaker provided to a substation or a switching station.
An example of a conventional switching device is described in Japanese Unexamined Patent Publication 2001-283691. An operating apparatus of the switching device described in this publication uses coil springs as a drive source for breaking and closing an electric current. Then, in a turn on state, respective springs are compressed to hold driving energy, while when an open/close command is issued, the driving energy of the springs is released so as to open/close a contact. At the time of opening/closing the contact, the contact is closed and a breaking spring is compressed using a cam.
An example of an operating apparatus of a circuit breaker which opens or closes the contact without using a cam is described in Japanese Unexamined Patent Publication 2002-216595. In the operating device described in the publication, for shortening time from closing of an opening/closing contact to starting of a next closing operation, an operating apparatus includes first and second breaking levers and an closing lever. Then, the first breaking lever is connected to the open/close contact and is imparted with a torque in the counterclockwise direction due to a torsion bar for a breaking circuit, while the second breaking lever is connected to the first breaking lever by way of a link device. The closing lever is imparted with a torque in the clockwise direction by a torsion bar for a closing circuit by way of a lever.
An example of an operating apparatus which opens/closes a switching device using an electric energy is described in Japanese Unexamined Patent Publication 2002-532842 through PCT. The operating device described in the publication is served for an electric switching device for high voltage or intermediate voltage such as a circuit breaker and includes an electrically-operated motor which is connected to a moving contact of the switching device. The electrically-operated motor, at the time of performing a breaking operation of the moving contact, accumulates a kinetic energy of a moving contact in a proper form or converts the kinetic energy and supplies the converted energy to a supply unit.
In the operating apparatus described in the above-mentioned Japanese Unexamined Patent Publication 2001-283691, a mechanism which holds or releases driving energies at the time of performing both of the breaking operation and the closing operation is necessary and hence, many parts are used whereby there exists a demand for further enhancement of miniaturization and reduction of weight. In the operating device described in Japanese Unexamined Patent Publication 2002-216595, although the operating time can be shortened, the consideration on the miniaturization and the enhancement of reliability of the operating apparatus by simplifying the operating mechanism is less than optimal. Still further, the electrically-operated motor of Japanese Unexamined Patent Publication 2002-532842 through PCT makes use of the electric energy at the time of performing the breaking operation and the closing operation and hence, when an operating voltage is lowered due to the occurrence of a trouble in a power source or the like in a substation, there may be a case that the switching operation becomes impossible.